package com.bilibili.dao;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;


public class BaseDao {
	public static final String URL="jdbc:mysql://127.0.0.1:3306/bilibili0?characterEncoding=UTF-8";
	public static final String USER="root";
	public static final String PASS="123456";
	public static final String DRIVER="com.mysql.cj.jdbc.Driver";
	
	public static Connection conn=null;
	public static PreparedStatement ps = null;
	
	
	/**
	 * 执行 添加 删除 修改的方法
	 * @param String SQL，Object占位符对应的值得数组 没有占位符传入null
	 * @RETURN int 影响行数 -1没有执行
	 * */
	public static int executeUpdate(String sql,Object[] param) {
		Connection conn=null;
		PreparedStatement ps = null;
		try {
			conn = getConn();
			ps = conn.prepareStatement(sql);//预编译sql
			if(param != null) {
				for (int i = 0; i < param.length; i++) {
					ps.setObject(i+1, param[i]);
				}
			}
			int num = ps.executeUpdate();//执行sql
			return num;
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}finally {
				closeAll(conn, ps);
		}
		return -1;
	}
	
	/**
	 * 执行 添加 删除 修改的方法
	 * @param String SQL
	 * @RETURN int 影响行数
	 * */
	public static int executeUpdate(String sql) {
		Connection conn=null;
		PreparedStatement ps = null;
		try {
			conn = getConn();
			ps = conn.prepareStatement(sql);//预编译sql
			int num = ps.executeUpdate();
			return num;
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}finally {
				closeAll(conn, ps);
		}
		return -1;
	}
	
	/**
	 * 获得数据库连接
	 * */
	public static Connection getConn() {
		try {
			Class.forName(DRIVER);
			Connection conn=DriverManager.getConnection(URL, USER, PASS);
			if(conn != null) {
				
			}
			return conn;
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (ClassNotFoundException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} 
		
		return null;
	}
	/**
	 * 释放资源Connection，PreparedStatement，ResultSet
	 * */
	public static void closeAll(Connection conn,Statement ps,ResultSet rs) {
		try {
			if(rs != null) rs.close();
			if(ps != null) ps.close();
			if(conn != null) conn.close();
		} catch (SQLException e) {e.printStackTrace();}
	}
	
	/**
	 * 释放资源Connection，PreparedStatement
	 * */
	public static void closeAll(Connection conn,PreparedStatement ps) {
		try {
			if(ps !=null) ps.close();
			if(conn !=null) conn.close();
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
	
	
	/**
	 * 查询
	 * @param sql
	 * @return ResultSet
	 * */	
	public static ResultSet queryResultSet(String sql) {
		BaseDao.conn=BaseDao.getConn();//打开连接
		ResultSet rs=null;
		try {
			BaseDao.ps= conn.prepareStatement(sql);
			rs = ps.executeQuery();				
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		return rs;
	}
	
	
	/**
	 * 查询案例
	 * 可借鉴
	 * */
	
//	public User query(String username, String userpass) {
//		Connection conn=BaseDao.getConn();
//		PreparedStatement s = null;
//		ResultSet rs = null;
//		try {
//			if(conn!=null) {
//				System.out.println("连接成功");
//			}
//			String sql = "select * from user where username='"+username+"' and userpass='"+userpass+"'";
//			System.out.println(sql);
//			s = conn.prepareStatement(sql);
//			rs =  s.executeQuery();
//			while(rs.next()) {
//				User user = new User();
//				user.setId(rs.getInt("id"));
//				user.setUsername(rs.getString("username"));
//				user.setUserpass(rs.getString("userpass"));
//				user.setSex(rs.getString("sex"));
//				user.setAge(rs.getInt("age"));
//				return user;
//			}
//			
//		} catch (SQLException e) {
//			// TODO Auto-generated catch block
//			e.printStackTrace();
//		}finally {			
//			BaseDao.closeAll(conn, s,rs);
//		}
//		return null;
//	}

//	public List<User> queryAll() {
//		Connection conn=BaseDao.getConn();//打开连接
//		String sql = "SELECT * FROM user";
//		List<User> list = new ArrayList<User>();
//		PreparedStatement ps= null;
//		ResultSet rs=null;
//		try {
//			ps= conn.prepareStatement(sql);
//			rs = ps.executeQuery();			
//			while(rs.next()) {
//				User user = new User();
//				user.setId(rs.getInt("id"));
//				user.setUsername(rs.getString("username"));
//				user.setUserpass(rs.getString("userpass"));
//				user.setSex(rs.getString("sex"));
//				user.setAge(rs.getInt("age"));
//				list.add(user);
//			}
//		} catch (SQLException e) {
//			// TODO Auto-generated catch block
//			e.printStackTrace();
//		}finally {
//			BaseDao.closeAll(conn, ps,rs);
//		}
//		return list;
//	}
	
	
}
